Humanity has a new older sister. A fossilized skeleton of Ardipithecus ramidus or "Ardi" predates Lucy by over a million years. The discovery has led to new insights about human evolution, suggesting previously unknown relationships to our chimpanzee brethren.
Charles Darwin, recognizing the similarities between humans and chimpanzees, postulated that we might someday find fossils of a "missing link," a creature that represented the evolutionary break between humans and chimps. The discovery of Ardi, however, suggests that when we do find that evolutionary break, the fossils we find will not be a blend of human and chimpanzee.
Researchers discovered Ar. ramidus near Aramis, Ethiopia, and have dated it as 4.4 million years old, considerably older than Lucy, who at 3.2 million years old was considered humanity's oldest relation. It's not clear whether humans are directly descended from this particular hominid, but it makes it clear that bipedal hominids are considerably older than previously thought.